list of commands and API

Hello everybody !!!
I'm peter from france (pierre en franšais)
I am looking for , and I haven't still find, a list of all the commands of HylaFAX,
and their effect.
I am looking since few days for HylaFAX, to use it on my AIX,
but I need to know two things :
- Is it possible to wright a driver for another kind of modem : we are using a specific kind of modem call Faxbox from DCE, a british company, and it has its own protocole, with a specific command language, using the T4 format.
- I need to know also if it is possible to wright API that allow other application to send fax ?
I'am programming from few days on Aix that's pearhaps why my questions are not very interesting !!!
Thanck you for your help
See you soon !!!
Bye !!